Left Atrial Expansion Index Predicts Left Ventricular Filling Pressure and Adverse Events in Acute Heart Failure With Severe Left Ventricular Dysfunction

• We assessed the clinical impacts of left atrium (LA) expansion index in 141 admitted patients with severe left ventricular (LV) systolic dysfunction.
• A logarithmic correlation between LA expansion index and LV filling pressure exists in patients with severe LV systolic dysfunction, either sinus rhythm or AF.
• LA expansion index is an independent predictor of adverse events and is useful for grading the risk of late outcome.

BackgroundThe power of left atrial (LA) parameters for predicting left ventricular (LV) filling pressure and adverse events in acute heart failure (HF) with severe LV dysfunction, either sinus rhythm or atrial fibrillation (AF), is not fully understood.Methods and ResultsEchocardiography was performed in 141 patients with acute decompensated congestive HF and LV ejection fraction <35%, including 42 with permanent AF. The LA expansion index was calculated as (Volmax − Volmin) × 100%/Volmin, where Volmax was defined as maximal and Volmin as minimal LA volume. Of 141 patients, invasive LV filling pressures within 12 hours of LA expansion index measurement were available in 109. The end points were 3-year frequencies of HF hospitalization and all-cause mortality. Over a median follow-up of 3.1 years, 74 participants (52.5%) reached the end points (sinus vs AF group: 48.5% vs 61.9%, respectively; P = .047). Multivariate analysis revealed that adverse events of both groups were only independently associated with age and LA expansion index. Rates of adverse events were proportional to LA expansion index. There was a good logarithmic relationship between LA expansion index and LV filling pressure, regardless of presence or absence of AF.ConclusionsLV filling pressure can be estimated well by LA expansion index, with or without AF. The LA expansion index predicts adverse events in HF patients with severe systolic dysfunction. (ClinicalTrials.gov number: NCT01307722).